arXiv:1002.3036 · Physics Letters B

Antihydrogen formation dynamics in a multipolar neutral anti-atom trap

Gorm Bruun Andresen, William Alan Bertsche, Paul David Bowe, C. C. Bray, Eoin Butler, Claudio Lenz Cesar, S. Chapman, M. Charlton, J. Fajans, M. Fujiwara, D. R. Gill, Jeffrey Scott Hangst, W. N. Hardy, R. Hayano, M. E. Hayden, Andrew James Humphries, Richard Hydomako, L. V. Jørgensen, Sean Kerrigan, L. L. Kurchaninov, Ricardo Lewis Lambo, N. Madsen, Paul J. Nolan, K. Olchanski, Art Olin, Alexander P. Povilus, Petteri Pusa, F. Robicheaux, E. Sarid, S. Seif El Nasr, Daniel Miranda Silveira, James William Storey, R. I. Thompson, Dirk Peter van der Werf, Jonathan Syrkin Wurtele, Y. Yamazaki

Published Jan 31, 2010• 41 citations

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Abstract

Antihydrogen production in a neutral atom trap formed by an octupole-based magnetic field minimum is demonstrated using field-ionization of weakly bound anti-atoms. Using our unique annihilation imaging detector, we correlate antihydrogen detection by imaging and by field-ionization for the first time. We further establish how field-ionization causes radial redistribution of the antiprotons during antihydrogen formation and use this effect for the first simultaneous measurements of strongly and weakly bound antihydrogen atoms. Distinguishing between these provides critical information needed in the process of optimizing for trappable antihydrogen. These observations are of crucial importance to the ultimate goal of performing CPT tests involving antihydrogen, which likely depends upon trapping the anti-atom.

DOI: 10.1016/j.physletb.2010.01.066

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